[Boost-users] [boost::numeric::functional::plus_base] Why the arguments are not const reference

Subject: [Boost-users] [boost::numeric::functional::plus_base] Why the arguments are not const reference
From: Kan Li (likan_999.student_at_[hidden])
Date: 2010-04-01 04:23:58

It seems like the operators define in boost::numeric::functional takes 
reference as argument instead of const reference.  Which makes it compile 
error if I use 

boost::numeric::functional::plus<int, int> op;
int n = op(1,1);

The way to work around is

boost::numeric::functional::plus<const int, const int> op;
int n = op(1,1);

This is very ugly and not makes much sense, compared to std::plus.  So is it a 
design flaw or is there some other reason for designing it in this way?